<template>
	<div class="app">
		<h2>我是App组件</h2>
		<h3>{{msg}}</h3>
	</div>
</template>

<script>
	export default {
		name:'App',
		data() {
			return {
				msg:'欢迎来学习！'
			}
		},
		mounted() {
			console.log(this.a)
		},
	}
</script>

<style>
	.app{
		background-color: gray;
		padding: 20px;
	}
</style>